Computer system management of power consumption is important to extend the operational ability of a battery and to reduce overall power consumption, which can be both fiscally and environmentally beneficial. Even for non-mobile computers, reducing power requirements is beneficial to save important global resources and prolong operation when relying on a battery backup system, such as during a utility power interruption.
Although most components of a computing system use power during system operation, the processor uses a disproportionate share of the system power. Many computer systems, including consumer based systems, include multiple processors and/or processors with multiple cores. Multiple processor enable the computers to execute increasing levels of work in parallel however additional processors may also increase power consumption. Most modern processors feature very low power idle power states, which may be applied per-core on a multi-core system, and which may be controlled by an operating system. In addition, processor frequency may be scaled on a per-core or per core group basis to reduce power usage by the system.